Refrigerator Fires - Why?

[waninae39]

as the fridge was not level, the gas vapour leaked onto the heater
as the vapour heated up, it eventual released its energy and caused the explosion

that is why many OEM's no longer use 3way fridges

[richard5933]

Originally Posted by waninae39

as the fridge was not level, the gas vapour leaked onto the heater
as the vapour heated up, it eventual released its energy and caused the explosion

that is why many OEM's no longer use 3way fridges

Originally Posted by waninae39

this what occurs when you DO NOT level a 3 way fridge
the explosion rocked the whole park

this photo was taken at the KOA in Sturgeon fall, ON, canada

More information is needed here, as this story doesn't make sense to me the way you're describing it.

First, propane is heavier than air. It will fall down. This is why the propane tanks in motor homes are mounted with open bottom compartments, just like the one in the photo showing the remaining horizontal tank.

The suggestion is that the gas vapor leaked to the heater. Which heater? The electric element in the fridge? Which gas vapor? The propane or leaking ammonia? If it's the propane, it's hard to see how enough could accumulate in a fridge compartment which has both upper and lower vents to cause that large of an explosion.

I'm not sure about the ammonia gas leak situation, but it seems that ammonia gas is lighter than air and should have vented through the upper vent.

So for me there still remains the question of how a fridge can cause that kind of explosion. My hunch is that there was a more serious problem/leak going on than just the fridge in this situation.

[eubank]

I agree with Richard. At least on my vintage Airstream, there was a good-sized hole in the plywood underlayment directly below the fridge, so if there was escaping gas, it would flow down and out, not up and around.

Richard is also right about mohos, but it's also more general. If you look at fifth-wheel trailers, they generally have vertical propane cylinders in enclosed, outside compartments, but the compartments are open to air at the bottom. Any leaking propane, which is heavier than air (as Richard notes) is released to the outside and does not build up inside an enclosed space in the RV.


Lynn

Originally Posted by richard5933

More information is needed here, as this story doesn't make sense to me the way you're describing it.

First, propane is heavier than air. It will fall down. This is why the propane tanks in motor homes are mounted with open bottom compartments, just like the one in the photo showing the remaining horizontal tank.

The suggestion is that the gas vapor leaked to the heater. Which heater? The electric element in the fridge? Which gas vapor? The propane or leaking ammonia? If it's the propane, it's hard to see how enough could accumulate in a fridge compartment which has both upper and lower vents to cause that large of an explosion.

I'm not sure about the ammonia gas leak situation, but it seems that ammonia gas is lighter than air and should have vented through the upper vent.

So for me there still remains the question of how a fridge can cause that kind of explosion. My hunch is that there was a more serious problem/leak going on than just the fridge in this situation.

[ITSNO60]

Here's the full story https://www.rvtravel.com/propane-exp...es-more-8n-r1/

No mention at all of a refrigerator being responsible, not sure where that info came from.

[dznf0g]

Originally Posted by ITSNO60

Here's the full story https://www.rvtravel.com/propane-exp...es-more-8n-r1/

No mention at all of a refrigerator being responsible, not sure where that info came from.

...a bunch of guys, the next morning, standing around, scratching their behinds, making up stories about their favorite theory. Gets repeated enough until one false theory becomes "fact". Happens a lot around here too.

[ITSNO60]

Originally Posted by waninae39

that is why many OEM's no longer use 3way fridges

I don't believe this for one minute either. Do you really think they care? It's all about the usual thing, money.

Most are jumping on the solar & electric bandwagon and giving you an inexpensive electric fridge, a lead chemistry battery and 100 watts of solar and sending you on your way as they count their money. They save money on construction costs and use it as a selling point giving you all the pros but none of the cons, a win win for the manufacturers and the sales persons.
IMHO of course.

[richard5933]

Originally Posted by waninae39

as the fridge was not level, the gas vapour leaked onto the heater
as the vapour heated up, it eventual released its energy and caused the explosion

that is why many OEM's no longer use 3way fridges

I believe the reasons are the compliance issues dealing with the chemical that's used to stabilize the ammonia system and prevent corrosion. If my memory is correct the chemical has been outlawed in some countries and compliance made very difficult/expensive in the remaining places.

[aftermath]

Originally Posted by ITSNO60

Here's the full story https://www.rvtravel.com/propane-exp...es-more-8n-r1/

No mention at all of a refrigerator being responsible, not sure where that info came from.

Thanks for this. I read the full story and it says it all.



It has been a short while since I have read one of the typical hysterical paranoiac attacks on the propane absorption fridge. This reference is a classic. First of all, the need to have a level fridge has nothing at all to do with gas escaping. There is no risk of a fire or an explosion if your fridge is not level. It if isn't level (enough) it will not work efficiently, that is it.



As far as Airstreams not having propane refrigerators any longer, safety wasn't the issue. After so many years of false information about fires and explosions, interest in options did increase. I am sticking my neck out here when I say "most" owners are the full hookup types. An all electric fridge does have its advantages as well documented in this forum and as long as you are plugged in, they are all that they claim. They also have their drawbacks too. I am angry that Airstream removed a buyer's choice. Instead of adding options, they removed one.

[richard5933]

Originally Posted by aftermath

Thanks for this. I read the full story and it says it all.

It has been a short while since I have read one of the typical hysterical paranoiac attacks on the propane absorption fridge. This reference is a classic. First of all, the need to have a level fridge has nothing at all to do with gas escaping. There is no risk of a fire or an explosion if your fridge is not level. It if isn't level (enough) it will not work efficiently, that is it. ....

There is also the risk of causing permanent damage. If the fridge is run too far out of level for too long a time it can create blockages inside the plumbing, creating a permanent cooling problem or even cause it to stop working.

[Bnystrom]

Originally Posted by aftermath

There is no risk of a fire or an explosion if your fridge is not level.

That's not true. If the fridge is not sufficiently level (IIRC, the spec for Norcold is +/- 3 degrees), it can cause overheating which absolutely can cause a fire.

[sfranklin]

Originally Posted by Bnystrom

That's not true. If the fridge is not sufficiently level (IIRC, the spec for Norcold is +/- 3 degrees), it can cause overheating which absolutely can cause a fire.

Over time. You all make it sound as if it's an immediate consequence. It's not. The overheating unit will boil away the rust inhibitors, and the unit can then rust from the inside out and THEN, when it does finally lose its structural integrity, a leak happens. How you are heating it makes somewhat of a difference. LP, almost an guaranteed fire. Electrical heating element, not a clear.

Two additional notes.

1) Absorption fridges have been around for nearly 100 years +/-. Originally, it was sulfuric acid they used in lieu of ammonia. Fires with these are nothing new, but to hear folks talk, it almost seems like the fires are rampant and if you have one and you are not level, boom or fire. Yes and no. When you are going up a mountain with a 7% grade, and the fridge is on LP and you are in the Rockies and spending several hours at grade, if this was as widespread as folks describe, we'd have fires and explosions in the hundreds per day.

https://en.wikipedia.org/wiki/Absorption_refrigerator

2) The absorption fridges though woefully inefficient and regardless of safety devices placed into the design, eventually will all fail, it just takes longer with the safety devices installed. Fridge defend and whatever Dometic built into the newer units (as I talked about earlier) just kick the can down the road. Steel rusts. You take your RV near the ocean? Tow in snow and expose to salt, eventually the coils will rust from the outside in...and let's not forget these are rolling houses that after many years of travel, who knows what could happen...weak weld, imperfection in the coil at the time of construction. Few, if any of the built in safety features will protect you from this if the fridge is on LP (and possibly, though less likely when on AC using the heating element).

The best defense in this case is a good offense. By all means, get a fridge defend, but also put a halon or equiv fire extinguisher into the rear cavity that can automatically discharge at 165F +/-, this will give you a fighting chance, but also be proactive. Look at the guts back there. Keep it clean. I can't tell you how many folks just fire and forget and you look inside and it's simply filthy. Folks love to put fans back there and a good number of folks just throw one in there that is always on if the fridge is on. Put it in line with a heat switch. If you don't, you in essence fan the flames should a fire break out.

I'm not loosing sleep on fridge fires. I am proactive and even though I am, I realize nothing comes with 100% certainty. Heck, I would never walk out my front door, let along lug an 8800lb RV 4000 miles a season. Your risk tolerance may be different than mine, but in 25 years of RVing as an adult, and another 10 RVing as a kid before that...I have had some exp with the systems placed into RVs. I do wholeheartedly acknowledge there are issues with absorption fridges and don't mean to sound flippant about their shortcomings, as there are some real serious ones out there, but I also am not screaming fire in a theater either.

[Bnystrom]

Originally Posted by sfranklin

Over time. You all make it sound as if it's an immediate consequence. It's not.

Nobody said that. The point is that you should avoid running the fridge out-of-level so you don't create the circumstances for premature failure.

When you are going up a mountain with a 7% grade, and the fridge is on LP and you are in the Rockies and spending several hours at grade...

In situations like that, it's wise to shut off the fridge. It will stay cold for quite a while.

The absorption fridges though woefully inefficient...

While they may be slow to cool down, they're actually very efficient, using little electrical power and barely sipping propane. Compressor fridges, by comparison, cool faster, but drain batteries quickly.

I'm not loosing sleep on fridge fires.

Nor am I. A little prevention goes a long way.

[richard5933]

Driving on steep mountain passes, according to the manual, isn't a problem as the constant motion keeps the type of crystallization and blockage from occurring.

[Bnystrom]

I hadn't seen that, so good to know!

[sfranklin]

Originally Posted by Bnystrom

Nobody said that. The point is that you should avoid running the fridge out-of-level so you don't create the circumstances for premature failure.

In situations like that, it's wise to shut off the fridge. It will stay cold for quite a while.

While they may be slow to cool down, they're actually very efficient, using little electrical power and barely sipping propane. Compressor fridges, by comparison, cool faster, but drain batteries quickly.
.

That is not what you alluded to or perhaps did not mean to as you did not say at the time "so you don't have premature failure":

Originally Posted by Bnystrom

That's not true. If the fridge is not sufficiently level (IIRC, the spec for Norcold is +/- 3 degrees), it can cause overheating which absolutely can cause a fire.

The comment at face value read to me that if you are not level you are going to have a fire. That to me is a generalization as there are a lot of RVers that have not leveled regularly to the +/- 3 degrees and not had a fire, where I know of one person who did level the 4-5 year old trailer, regularly, and it still caught fire and killed his dog and let's be honest, the fridge is going to fail no matter how much you baby it. It's not a matter of if, it's a matter of when and one hopes that when that when day comes, it's not actively running on LP, which is why I keep an automatic halon extinguisher that discharges at 165F in the back end of the fridge- and i have a bunch of safety things on that fridge that only lessen the odds of a fire, nothing one does will totally eliminate the possibility of an LP absorption fridge fire.

If a person is consistently out of level, and they have to turn it off and have that large lag as you yourself describe for it to re-cool, an absorption fridge is simply not for that person. In the older days the motto was if you are comfortable, the absorption fridge will be too. My opinion, for what its worth is that the amish cooling units are far superior to the factory norcold and dometic units available today and may take a bit more abuse, but that's a whole different thread discussion.

We can go round and round on efficiency, and it is true that 12v compressors do chew up a battery faster than you can say battery, which is why I opted for a trailer that had an absorption fridge as I boondock extensively. Sure the fridge sips LP and uses far fewer amps than the 12 compressor fridge, however, my take is that the thermal transfer to get the same cooling is nowhere near as efficient in terms of cooling, not power consumption, which is why 12v fridges cool so much faster.

The days for absorption fridges are woefully numbered. Even LP ovens are becoming more and more rare and there is talk of phasing out natural gas furnaces and stoves in homes. How far that goes I can only guess, but in terms of RV absorption fridges, I accept the risks and do my part to not only minimize the possibility, but also have active systems in place should those safety devices already on the fridge fail, as there are a certain key variables to an actual fire to start. It is not a forgone conclusion that every RV LP capable fridge abused, not leveled or not will have an end resulting in a fire...granted a much higher percentage, but not absolute, particularly if the chain of events leading to it are not fully met. One such example is the unit evacuates its contents and there is no heat being applied as the newer fridges of the past 20 years do not run 24/7, they cycle. Still not zero, but also not 100% either.

[richard5933]

Originally Posted by richard5933

Driving on steep mountain passes, according to the manual, isn't a problem as the constant motion keeps the type of crystallization and blockage from occurring.

Originally Posted by Bnystrom

I hadn't seen that, so good to know!

Here's the piece from my manual which discussed it. I assume that most absorption fridges have a similar statement bother about the leveling requirement and the bit about use while moving.

[aftermath]

Richard, I did read a similar warning about running my fridge as well. I will go back to my original statement and say that running "out of level" isn't going to cause your fridge to blowup. Now, if you do this for a long, very long time, it will certainly cause issues and down the road, a long way down the road other serious conditions "might" happen. My main point here is to make folks less fearful of running their absorption refrigerators. When done properly they will give you many years of service.


More specifically, the false statements made about the blown up motorhome had something to do with a fridge out of level, is quite damaging. Running your fridge while driving is another issue that is often misrepresented. As in all things, use your head, follow the recommended guidelines and you won't be at risk.

[aftermath]

You won't be at any additional risk, is what I should have said. We are all at risk every time we travel down the road, pulling our trailers, in traffic and many times at high speed. There is the real issue.